24/09/2025
Patents exist to reward innovation. They can act as a valuable tool for organizations wishing to protect their innovative efforts, by allowing them to prevent or restrict unauthorized exploitation of a patented invention in a given country or territory.
For most industries, the territorial reach of a patent is rarely an important question; exploitation of an invention either takes place in a country in which a patent application has been filed, or it happens elsewhere. However, in offshore industries, much activity occurs far out to sea, well beyond conventional land or coastal borders. This is particularly true for the North Sea, where significant oil and gas and renewables installations reside on the continental shelf. So, how does the territorial nature of patents work in such circumstances? And what can offshore innovators do to protect themselves in such an environment? In this article, we will explore the answers to these key questions.
Territorial Extent of a UK Patent
The starting point for considering the territory of a UK patent is The UK Patents Act 1977. This specifies that a UK patent covers the entire landmass of the United Kingdom, as well as that of the Isle of Man. It also tells us that a UK patent covers the territorial waters of the UK, with these being defined as reaching up to 12 nautical miles (about 22 kilometres) from the coastline. So, a UK patent can certainly be infringed at sea, provided the infringement occurs within this 12 mile coastal limit.
But, as illustrated by the map below, 12 nautical miles only represents a fraction of the North Sea basin. Much of the UK’s oil, gas, wind and carbon capture installations are or will be located far beyond this boundary. Can a UK patent reach out to these? The answer is effectively “yes”, “no”, and “maybe”; it all depends on the circumstances of the installation and the patent or invention in question.
Figure 1: Map of the UK territorial waters and continental shelf. [1]
To understand why, we need to look at the Petroleum Act 1998. This Act of Parliament concerns the licensing, operation and decommissioning of offshore installations in regions of the continental shelf. Within the Petroleum Act are provisions for extending UK law to activities taking place on, under or above such installations. The UK Patents Act contains an important reference to the Petroleum Act, and sets out how patent protection may also be extended to the continental shelf for certain activities. The provisions of both Acts are complex and far from straightforward in the way they interlink. However, in simple terms, the combination of these Acts offer a UK patent owner a way to extend the territory covered by their UK patent, but crucially, this is only enabled under certain circumstances for certain activities.
But what are such circumstances and activities? Well, as the word ‘petroleum’ suggests, the activities are ones you would typically expect of an oil and gas installation, and include in a general sense:
the exploration of, or the exploitation of the natural resources of the shore or bed of waters, or the subsoil beneath it [2]
As well as this general definition, the Petroleum Act also lists certain specific activities [3] which could lead to patent infringement on the continental shelf, namely:
a) The exploitation or exploration of mineral resources in or under the shore or bed of waters to which this section applies;
b) The exploration of any place in, under or over such waters with a view to the storage of gas in such a place;
c) The conversion of any place in, under or over waters to which this section applies for the purpose of storing gas;
d) The storage of gas in, under or over such waters or the recovery of gas so stored;
e) The unloading of gas at any place in, under or over such waters;
f) The conveyance of things by means of a pipe, or system of pipes, constructed or placed on, in or under the shore or bed of such waters; and
g) The provision of accommodation for persons who work on or from an installation which is or has been maintained, or is intended to be established, for the carrying on of an activity above.
For those in the industry, it is easy to see how activities a) to g) can be carried out in an oil and gas context. As such, UK law is fairly clear on how the territorial reach of a patent can be extended for certain oil and gas activities; hence why the answer “yes” should generally be given to the question posed above for such circumstances.
However, legislation is always open to interpretation, and there are arguably ways to read activities a) to g) in a manner that would mean they are not solely restricted to oil and gas. This introduces ambiguity to the law and opens up the possibility for certain non-oil and gas activities in the North Sea being covered by the Petroleum Act’s territorial extension. It is for this reason that the answers “no” and “maybe” can also be given to the question posed above.
Wind Installations – an example of a “no” or a “probably not”
In the context of wind installations, this ambiguity was notably tested in a 2022 patent dispute between Siemens and GE at the England and Wales High Court [4]. The dispute concerned the territory of “Dogger Bank”, a large sand bank about 55 nautical miles (about 100 kilometres) off the east coast of England. Siemens asserted that the installation of turbines at Dogger Bank infringed on one of their UK patents, because the Petroleum Act extended the territorial reach of that patent to activities occurring on that part of the continental shelf.
A key element in the dispute hinged on whether installing towers for the Dogger Bank turbines was an activity “connected with the exploration of, or the exploitation of the natural resources of, the shore or bed of waters to which this section applies or the subsoil beneath it” within the meaning of the Petroleum Act.
The court heard arguments from both parties and ultimately concluded that installation of the towers could not be considered to constitute “exploitation” of the kind required by the Petroleum Act. In particular, the court decided that no “natural resources” are actually exploited by installing wind turbines, but rather what is taken advantage of is the mere existence of the sea bed and subsoil beneath it. The Judge held that “taking living or non-living resources like hydrocarbons or seaweed and doing something with them is “exploitation”, but that merely drilling out some rock and then not doing anything with it (the rock) is not”.
The case therefore provided a good example of a situation where the Petroleum and Patents Acts were not able to broaden the territorial reach of a UK patent. However, it is important to note that the decision was limited to the specific set of circumstances presented to the court. The Judge did not look at the provisions more broadly and speculate on what wind related scenarios (if any) would be able to benefit from the relevant provisions. As a result, there remains untested questions over whether other renewable energy or sustainability related installations could benefit from the territorial extension to patent protection offered by the Petroleum Act. Put simply, the Siemens v GE case sets a high bar, but there may be other non-oil and gas scenarios which offer more promise.
Carbon Capture – an example of a promising “maybe”?
For example, one promising area for UK patent owners is carbon capture, and more specifically, carbon storage. This is because activity d) noted above refers to “the storage of gas [in, under or over] such waters or the recovery of gas so stored”, and the Petroleum Act explicitly states that the gas can be “carbon dioxide”. The Petroleum Act also states that storing gas includes storing gas with a view to its permanent disposal [5].
There is a growing interest, both globally and in the UK, for carbon capture and storage, and technological innovation in this area (including in offshore environments) is increasing. Indeed, the UK’s North Sea Transition Authority (NSTA) has already awarded over 20 licenses for offshore carbon storage sites, and has suggested there are more to come. Having UK patent protection extend to such offshore sites could therefore become very important in the future as competition and implementation intensifies.
Figure 2: Map with examples of sites for carbon dioxide (CO2) appraisal and storage licences on the UK Continental Shelf [6]
Carbon capture and storage innovations therefore provide the basis for the “maybe” answer given above, since they are arguably more likely to benefit from the provisions than wind innovations, but have not yet been proven and tested like oil and gas.
Are there more pragmatic solutions for offshore innovators?
As noted above, the provisions of the Petroleum and Patents Act are complex and remain untested for many use cases. They therefore present interesting opportunities for offshore innovators, but they should not be solely relied on.
More pragmatic solutions lie in the way an invention is captured in a patent and how its protection is actually defined. Wherever possible, the invention should be defined in the form it takes when onshore, so that patent owners can enforce against infringements occurring on land or at ports before the invention is deployed in the North Sea. For example, if the invention concerns a collection of components which are assembled offshore to form part of a wind turbine, the patent could protect “a kit of parts comprising the components to be assembled”. This makes anyone holding the unassembled kit on land or in a port a direct infringer, and thus avoids any need to consider the complexities of the Petroleum Act.
Patent owners can also benefit from the fact that patent infringement is not limited to the making, using or selling of an invention; it also covers the acts of importing and exporting. Some offshore assets may not be made in the UK, but will nevertheless need to pass through UK ports before they can be deployed on the continental shelf. Using a patent to prevent such importation could offer a patent owner another way to protect their innovative endeavours.
Finally, even if the invention can only be defined in the form it takes when assembled offshore, it may still be possible for a patent to be enforced against acts occurring onshore. This is because UK law includes provisions known as ‘indirect infringement’. These allow a patent owner to act against a person who supplies or offers to supply the “essential means” for putting an invention into effect, where they know (or it is obvious) that those essential means are suitable for and intended to be used in making the patented invention.
This is important in the offshore context because different companies often supply parts or technology rather than building the entire system. For instance, if a supplier provides a specialised coupling or control system that is only useful for operating a patented offshore process, the patent owner may have a claim against them even if the supplier never assembles the complete invention themselves. Drafting a patent that clearly defines what counts as an “essential means” could therefore help to strengthen the scope of enforceability in practice.
At Reddie & Grose LLP, we have the specialist knowledge and experience required to draft meaningful and commercially useful patents for our clients, taking into account an understanding of how and where inventions are to be deployed, as well as a detailed understanding of the underlying technical concepts. If you work in the field of carbon capture, or more generally in the offshore energy sector, and would like to know how you can best protect your innovations, please get in contact with one of our specialist attorneys.
This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking any action in reliance on it.
[1] A review of methodologies that could be used to formulate ecologically meaningful targets for marine habitat coverage within the UK MPA network, Carlo Rondinini, Sapienza University of Rome
[2] Section 11(2)(a) of the Petroleum Act 1998
[3] Sections 11(2)(b) and 11(3) of the Petroleum Act 1998
[4] Siemens v GE [2022] EWHC 3034 (Pat)
[5] Sections 11(9)(b) and 11(3A) of the Petroleum Act 1998
[6] Source: https://www.nstauthority.co.uk/the-move-to-net-zero/ccs/
